diff --git a/Changes b/Changes
index 24bca0beb..81a383916 100644
--- a/Changes
+++ b/Changes
@@ -16,6 +16,8 @@ indicates the contributor was also the author of the fix; Thanks!
 
 ***  Support declarations in loop initializers, bug172.  [by Byron Bradley]
 
+***  Support $test$plusargs and $value$plusargs, but see the docs!
+
 ***  Add VARHIDDEN warning when signal name hides module name.
 
 **** Fix MinGW compilation, bug184. [by Shankar Giri]
diff --git a/bin/verilator b/bin/verilator
index 27d06e877..55d14a92b 100755
--- a/bin/verilator
+++ b/bin/verilator
@@ -768,6 +768,7 @@ We'll compile this example into C++.
       #include "Vour.h"
       #include "verilated.h"
       int main(int argc, char **argv, char **env) {
+	  Verilated::commandArgs(argc, argv);
           Vour* top = new Vour;
           while (!Verilated::gotFinish()) { top->eval(); }
           exit(0);
@@ -825,6 +826,7 @@ This is an example similar to the above, but using SystemPerl.
     cat <<EOF >sc_main.cpp
       #include "Vour.h"
       int sc_main(int argc, char **argv) {
+	  Verilated::commandArgs(argc, argv);
           sc_clock clk ("clk",10, 0.5, 3, true);
           Vour* top;
           top = new Vour("top");   // SP_CELL (top, Vour);
@@ -1080,7 +1082,9 @@ example:
 	    return main_time;
 	}
 
-	int main() {
+	int main(int argc, char** argv) {
+	    Verilated::commandArgs(argc, argv);   // Remember args
+
 	    top = new Vtop;		// Create instance
 
 	    top->reset_l = 0;		// Set some inputs
@@ -1784,6 +1788,22 @@ arrays.
 
 Treated as $time.
 
+=item $test$plusargs, $value$plusargs
+
+Supported, but the instantiating C++/SystemC testbench must call
+
+    Verilated::commandArgs(argc, argv);
+
+to register the command line before calling $test$plusargs or
+$value$plusargs.
+
+=item $timeformat
+
+Not supported as Verilator needs to determine all formatting at compile
+time.  Generally you can just ifdef them out for no ill effect.  Note also
+VL_TIME_MULTIPLER can be defined at compile time to move the decimal point
+when displaying all times, model wide.
+
 =back
 
 =head1 ERRORS AND WARNINGS
diff --git a/include/verilated.cpp b/include/verilated.cpp
index 8338f4ddb..65f23c7ea 100644
--- a/include/verilated.cpp
+++ b/include/verilated.cpp
@@ -25,6 +25,7 @@
 
 #include "verilated.h"
 #include <cctype>
+#include <vector>
 
 #define VL_VALUE_STRING_MAX_WIDTH 1024	///< Max static char array for VL_VALUE_STRING
 
@@ -37,6 +38,38 @@ bool Verilated::s_calcUnusedSigs = false;
 bool Verilated::s_gotFinish = false;
 bool Verilated::s_assertOn = true;
 
+//===========================================================================
+// Local Implementation Globals
+// (Not in Verilated as they can be slow, and we want to mimimize the STL imports)
+
+class VerilatedImp {
+protected:
+    friend class Verilated;
+    typedef vector<string> ArgVec;
+    static ArgVec	s_argVec;	// Argument list
+    static bool		s_argVecLoaded;	// Ever loaded argument list
+    // METHODS
+public:  // But only for this C file
+    static string argPlusMatch(const char* prefixp) {
+	int len = strlen(prefixp);
+	if (!s_argVecLoaded) {
+	    s_argVecLoaded = true;  // Complain only once
+	    vl_fatal("unknown",0,"",
+		     "%Error: Verilog called $test$plusargs or $value$plusargs without"
+		     " testbench C first calling Verilated::commandArgs(argc,argv).");
+	}
+	for (ArgVec::iterator it=s_argVec.begin(); it!=s_argVec.end(); ++it) {
+	    if ((*it)[0]=='+') {
+		if (0==strncmp(prefixp, it->c_str()+1, len)) return *it;
+	    }
+	}
+	return "";
+    }
+};
+
+VerilatedImp::ArgVec  VerilatedImp::s_argVec;
+bool	VerilatedImp::s_argVecLoaded = false;
+
 //===========================================================================
 // User definable functions
 
@@ -441,6 +474,32 @@ static inline void _vl_vsss_setbit(WDataOutP owp, int obits, int lsb, int nbits,
 	VL_ASSIGNBIT_WI(0, lsb, owp, ld & 1);
     }
 }
+static inline void _vl_vsss_based(WDataOutP owp, int obits, int baseLog2, const char* strp, int posstart, int posend) {
+    // Read in base "2^^baseLog2" digits from strp[posstart..posend-1] into owp of size obits.
+    int lsb = 0;
+    for (int i=0, pos=posend-1; i<obits && pos>=posstart; pos--) {
+	switch (tolower (strp[pos])) {
+	case 'x': case 'z': case '?': //FALLTHRU
+	case '0': lsb += baseLog2; break;
+	case '1': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  1); lsb+=baseLog2; break;
+	case '2': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  2); lsb+=baseLog2; break;
+	case '3': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  3); lsb+=baseLog2; break;
+	case '4': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  4); lsb+=baseLog2; break;
+	case '5': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  5); lsb+=baseLog2; break;
+	case '6': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  6); lsb+=baseLog2; break;
+	case '7': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  7); lsb+=baseLog2; break;
+	case '8': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  8); lsb+=baseLog2; break;
+	case '9': _vl_vsss_setbit(owp,obits,lsb, baseLog2,  9); lsb+=baseLog2; break;
+	case 'a': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 10); lsb+=baseLog2; break;
+	case 'b': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 11); lsb+=baseLog2; break;
+	case 'c': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 12); lsb+=baseLog2; break;
+	case 'd': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 13); lsb+=baseLog2; break;
+	case 'e': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 14); lsb+=baseLog2; break;
+	case 'f': _vl_vsss_setbit(owp,obits,lsb, baseLog2, 15); lsb+=baseLog2; break;
+	case '_': break;
+	}
+    }
+}
 
 IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		  int fbits, WDataInP fromp,  // Else if a sscanf
@@ -480,7 +539,6 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		// Deal with all read-and-scan somethings
 		// Note LSBs are preserved if there's an overflow
 		const int obits = va_arg(ap, int);
-		int lsb = 0;
 		WData qowp[2];
 		WDataOutP owp = qowp;
 		if (obits > VL_QUADSIZE) {
@@ -500,6 +558,7 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		    _vl_vsss_read(fp,floc,fromp, tmp, NULL);
 		    if (!tmp[0]) goto done;
 		    int pos = strlen(tmp)-1;
+		    int lsb = 0;
 		    for (int i=0; i<obits && pos>=0; pos--) {
 			_vl_vsss_setbit(owp,obits,lsb, 8, tmp[pos]); lsb+=8;
 		    }
@@ -507,7 +566,7 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		}
 		case 'd': { // Signed decimal
 		    _vl_vsss_skipspace(fp,floc,fromp);
-		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789+-xz?_");
+		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789+-xXzZ?_");
 		    if (!tmp[0]) goto done;
 		    vlsint64_t ld;
 		    sscanf(tmp,"%lld",&ld);
@@ -517,7 +576,7 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		case 't': // FALLTHRU  // Time
 		case 'u': { // Unsigned decimal
 		    _vl_vsss_skipspace(fp,floc,fromp);
-		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789+-xz?_");
+		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789+-xXzZ?_");
 		    if (!tmp[0]) goto done;
 		    QData ld;
 		    sscanf(tmp,"%llu",&ld);
@@ -526,67 +585,23 @@ IData _vl_vsscanf(FILE* fp,  // If a fscanf
 		}
 		case 'b': {
 		    _vl_vsss_skipspace(fp,floc,fromp);
-		    _vl_vsss_read(fp,floc,fromp, tmp, "01xz?_");
+		    _vl_vsss_read(fp,floc,fromp, tmp, "01xXzZ?_");
 		    if (!tmp[0]) goto done;
-		    int pos = strlen(tmp)-1;
-		    for (int i=0; i<obits && pos>=0; pos--) {
-			switch(tmp[pos]) {
-			case 'x': case 'z': case '?': //FALLTHRU
-			case '0': lsb++; break;
-			case '1': _vl_vsss_setbit(owp,obits,lsb, 1, 1); lsb++; break;
-			case '_': break;
-			}
-		    }
+		    _vl_vsss_based(owp,obits, 1, tmp, 0, strlen(tmp));
 		    break;
 		}
 		case 'o': {
 		    _vl_vsss_skipspace(fp,floc,fromp);
-		    _vl_vsss_read(fp,floc,fromp, tmp, "01234567xz?_");
+		    _vl_vsss_read(fp,floc,fromp, tmp, "01234567xXzZ?_");
 		    if (!tmp[0]) goto done;
-		    int pos = strlen(tmp)-1;
-		    for (int i=0; i<obits && pos>=0; pos--) {
-			switch(tmp[pos]) {
-			case 'x': case 'z': case '?': //FALLTHRU
-			case '0': lsb+=3; break;
-			case '1': _vl_vsss_setbit(owp,obits,lsb, 3, 1); lsb+=3; break;
-			case '2': _vl_vsss_setbit(owp,obits,lsb, 3, 2); lsb+=3; break;
-			case '3': _vl_vsss_setbit(owp,obits,lsb, 3, 3); lsb+=3; break;
-			case '4': _vl_vsss_setbit(owp,obits,lsb, 3, 4); lsb+=3; break;
-			case '5': _vl_vsss_setbit(owp,obits,lsb, 3, 5); lsb+=3; break;
-			case '6': _vl_vsss_setbit(owp,obits,lsb, 3, 6); lsb+=3; break;
-			case '7': _vl_vsss_setbit(owp,obits,lsb, 3, 7); lsb+=3; break;
-			case '_': break;
-			}
-		    }
+		    _vl_vsss_based(owp,obits, 3, tmp, 0, strlen(tmp));
 		    break;
 		}
 		case 'x': {
 		    _vl_vsss_skipspace(fp,floc,fromp);
-		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789abcdefxz?_");
+		    _vl_vsss_read(fp,floc,fromp, tmp, "0123456789abcdefABCDEFxXzZ?_");
 		    if (!tmp[0]) goto done;
-		    int pos = strlen(tmp)-1;
-		    for (int i=0; i<obits && pos>=0; pos--) {
-			switch(tmp[pos]) {
-			case 'x': case 'z': case '?': //FALLTHRU
-			case '0': lsb+=4; break;
-			case '1': _vl_vsss_setbit(owp,obits,lsb, 4,  1); lsb+=4; break;
-			case '2': _vl_vsss_setbit(owp,obits,lsb, 4,  2); lsb+=4; break;
-			case '3': _vl_vsss_setbit(owp,obits,lsb, 4,  3); lsb+=4; break;
-			case '4': _vl_vsss_setbit(owp,obits,lsb, 4,  4); lsb+=4; break;
-			case '5': _vl_vsss_setbit(owp,obits,lsb, 4,  5); lsb+=4; break;
-			case '6': _vl_vsss_setbit(owp,obits,lsb, 4,  6); lsb+=4; break;
-			case '7': _vl_vsss_setbit(owp,obits,lsb, 4,  7); lsb+=4; break;
-			case '8': _vl_vsss_setbit(owp,obits,lsb, 4,  8); lsb+=4; break;
-			case '9': _vl_vsss_setbit(owp,obits,lsb, 4,  9); lsb+=4; break;
-			case 'a': _vl_vsss_setbit(owp,obits,lsb, 4, 10); lsb+=4; break;
-			case 'b': _vl_vsss_setbit(owp,obits,lsb, 4, 11); lsb+=4; break;
-			case 'c': _vl_vsss_setbit(owp,obits,lsb, 4, 12); lsb+=4; break;
-			case 'd': _vl_vsss_setbit(owp,obits,lsb, 4, 13); lsb+=4; break;
-			case 'e': _vl_vsss_setbit(owp,obits,lsb, 4, 14); lsb+=4; break;
-			case 'f': _vl_vsss_setbit(owp,obits,lsb, 4, 15); lsb+=4; break;
-			case '_': break;
-			}
-		    }
+		    _vl_vsss_based(owp,obits, 4, tmp, 0, strlen(tmp));
 		    break;
 		}
 		default:
@@ -851,6 +866,48 @@ void VL_READMEM_W(bool hex, int width, int depth, int array_lsb, int fnwords,
     }
 }
 
+IData VL_TESTPLUSARGS_I(const char* formatp) {
+    string match = VerilatedImp::argPlusMatch(formatp);
+    if (match == "") return 0;
+    else return 1;
+}
+
+IData VL_VALUEPLUSARGS_IW(int rbits, const char* prefixp, char fmt, WDataOutP rwp) {
+    string match = VerilatedImp::argPlusMatch(prefixp);
+    const char* dp = match.c_str() + 1 /*leading + */ + strlen(prefixp);
+    if (match == "") return 0;
+    VL_ZERO_RESET_W(rbits, rwp);
+    switch (tolower(fmt)) {
+    case '%':
+	break;
+    case 'd':
+	vlsint64_t ld;
+	sscanf(dp,"%lld",&ld);
+	VL_SET_WQ(rwp,ld);
+	break;
+    case 'b':
+	_vl_vsss_based(rwp,rbits, 1, dp, 0, strlen(dp));
+	break;
+    case 'o':
+	_vl_vsss_based(rwp,rbits, 3, dp, 0, strlen(dp));
+	break;
+    case 'h': //FALLTHRU
+    case 'x':
+	_vl_vsss_based(rwp,rbits, 4, dp, 0, strlen(dp));
+	break;
+    case 's':
+	for (int i=0, lsb=0, pos=strlen(dp)-1; i<rbits && pos>=0; pos--) {
+	    _vl_vsss_setbit(rwp,rbits,lsb, 8, dp[pos]); lsb+=8;
+	}
+	break;
+    default:  // Compile time should have found all errors before this
+	vl_fatal (__FILE__, __LINE__, "", "$value$plusargs format error");
+	break;
+    }
+    _VL_CLEAN_INPLACE_W(rbits,rwp);
+    return 1;
+}
+
 //===========================================================================
 // Verilated:: Methods
 
@@ -870,6 +927,15 @@ const char* Verilated::catName(const char* n1, const char* n2) {
     return strp;
 }
 
+void Verilated::commandArgs(int argc, const char** argv) {
+    VerilatedImp::s_argVec.clear();
+    for (int i=0; i<argc; i++) {
+	VerilatedImp::s_argVec.push_back(argv[i]);
+    }
+    // Can't just test later for empty vector, no arguments is ok
+    VerilatedImp::s_argVecLoaded = true;
+}
+
 //===========================================================================
 // VerilatedModule:: Methods
 
diff --git a/include/verilated.h b/include/verilated.h
index 82bfedf6f..95dccec0f 100644
--- a/include/verilated.h
+++ b/include/verilated.h
@@ -166,6 +166,9 @@ public:
     /// Enable/disable assertions
     static void assertOn(bool flag) { s_assertOn=flag; }
     static bool assertOn() { return s_assertOn; }
+    /// Command line arguments
+    static void commandArgs(int argc, const char** argv);
+    static void commandArgs(int argc, char** argv) { commandArgs(argc,(const char**)argv); }
 };
 
 //=========================================================================
@@ -218,6 +221,9 @@ extern IData VL_SSCANF_IIX(int lbits, IData ld, const char* formatp, ...);
 extern IData VL_SSCANF_IQX(int lbits, QData ld, const char* formatp, ...);
 extern IData VL_SSCANF_IWX(int lbits, WDataInP lwp, const char* formatp, ...);
 
+extern IData VL_TESTPLUSARGS_I(const char* formatp);
+extern IData VL_VALUEPLUSARGS_IW(int rbits, const char* prefixp, char fmt, WDataOutP rwp);
+
 //=========================================================================
 // Base macros
 
@@ -1420,6 +1426,26 @@ static inline WDataOutP VL_COND_WIWW(int obits, int, int, int,
     return(owp);
 }
 
+//======================================================================
+// System Functions
+
+inline IData VL_VALUEPLUSARGS_IQ(int rbits, const char* prefixp, char fmt, QData& ldr) {
+    WData wd[2]; IData v=VL_VALUEPLUSARGS_IW(rbits,prefixp,fmt,wd); if (v) ldr=VL_SET_QW(wd);
+    return v;
+}
+inline IData VL_VALUEPLUSARGS_II(int rbits, const char* prefixp, char fmt, CData& ldr) {
+    QData qd; IData v=VL_VALUEPLUSARGS_IQ(rbits,prefixp,fmt,qd); if (v) ldr=qd;
+    return v;
+}
+inline IData VL_VALUEPLUSARGS_II(int rbits, const char* prefixp, char fmt, SData& ldr) {
+    QData qd; IData v=VL_VALUEPLUSARGS_IQ(rbits,prefixp,fmt,qd); if (v) ldr=qd;
+    return v;
+}
+inline IData VL_VALUEPLUSARGS_II(int rbits, const char* prefixp, char fmt, IData& ldr) {
+    QData qd; IData v=VL_VALUEPLUSARGS_IQ(rbits,prefixp,fmt,qd); if (v) ldr=qd;
+    return v;
+}
+
 //======================================================================
 // Constification
 
diff --git a/src/V3AstNodes.h b/src/V3AstNodes.h
index 1fc96264b..b1377b091 100644
--- a/src/V3AstNodes.h
+++ b/src/V3AstNodes.h
@@ -1558,6 +1558,56 @@ public:
     AstNode*	msbp() const { return op4p()->castNode(); }
 };
 
+struct AstValuePlusArgs : public AstNodeMath {
+    // Parents: expr
+    // Child: variable to set.  If NULL then this is a $test$plusargs instead of $value$plusargs
+private:
+    string	m_text;
+public:
+    AstValuePlusArgs(FileLine* fileline, const string& text, AstNode* exprsp)
+	: AstNodeMath (fileline), m_text(text) {
+	setOp1p(exprsp);
+    }
+    ASTNODE_NODE_FUNCS(ValuePlusArgs, VALUEPLUSARGS)
+    virtual string name()	const { return m_text; }
+    virtual string verilogKwd() const { return "$value$plusargs"; }
+    virtual string emitVerilog() { return verilogKwd(); }
+    virtual string emitC() { return "VL_VALUEPLUSARGS_%nq(%lw, %P, NULL)"; }
+    virtual bool isGateOptimizable() const { return false; }
+    virtual bool isPredictOptimizable() const { return false; }
+    virtual bool cleanOut() { return true; }
+    virtual V3Hash sameHash() const { return V3Hash(text()); }
+    virtual bool same(AstNode* samep) const {
+	return text()==samep->castValuePlusArgs()->text(); }
+    AstNode*	exprsp()	const { return op1p()->castNode(); }	// op1 = Expressions to output
+    void 	exprsp(AstNode* nodep)	{ setOp1p(nodep); }	// op1 = Expressions to output
+    string 	text()		const { return m_text; }	// * = Text to display
+    void 	text(const string& text) { m_text=text; }
+};
+
+struct AstTestPlusArgs : public AstNodeMath {
+    // Parents: expr
+    // Child: variable to set.  If NULL then this is a $test$plusargs instead of $value$plusargs
+private:
+    string	m_text;
+public:
+    AstTestPlusArgs(FileLine* fileline, const string& text)
+	: AstNodeMath (fileline), m_text(text) { }
+    ASTNODE_NODE_FUNCS(TestPlusArgs, TESTPLUSARGS)
+    virtual string name()	const { return m_text; }
+    virtual string verilogKwd() const { return "$test$plusargs"; }
+    virtual string emitVerilog() { return verilogKwd(); }
+    virtual string emitC() { return "VL_VALUEPLUSARGS_%nq(%lw, %P, NULL)"; }
+    virtual bool isGateOptimizable() const { return false; }
+    virtual bool isPredictOptimizable() const { return false; }
+    virtual bool cleanOut() { return true; }
+    virtual V3Hash sameHash() const { return V3Hash(text()); }
+    virtual bool same(AstNode* samep) const {
+	return text()==samep->castTestPlusArgs()->text(); }
+    string 	text()		const { return m_text; }	// * = Text to display
+    void 	text(const string& text) { m_text=text; }
+};
+
 struct AstGenFor : public AstNodeFor {
     AstGenFor(FileLine* fileline, AstNode* initsp, AstNode* condp,
 	   AstNode* incsp, AstNode* bodysp)
diff --git a/src/V3EmitC.cpp b/src/V3EmitC.cpp
index 92020be49..893d7b165 100644
--- a/src/V3EmitC.cpp
+++ b/src/V3EmitC.cpp
@@ -236,6 +236,59 @@ public:
     virtual void visit(AstSScanF* nodep, AstNUser*) {
 	displayNode(nodep, nodep->text(), nodep->exprsp(), true);
     }
+    virtual void visit(AstValuePlusArgs* nodep, AstNUser*) {
+	string prefix;
+	char format = '?';
+	bool pct=false;
+	int got=0;
+	for (const char* cp = nodep->text().c_str(); *cp; cp++) {
+	    if (pct) {
+		pct = false;
+		switch (tolower(*cp)) {
+		case '%':
+		    prefix += *cp;
+		    break;
+		case 'd': // FALLTHRU
+		case 'o': // FALLTHRU
+		case 'h': // FALLTHRU
+		case 'x': // FALLTHRU
+		case 'b': // FALLTHRU
+		case 's':
+		    got++; format = tolower(*cp);
+		    break;
+		case 'e': // FALLTHRU
+		case 'f': // FALLTHRU
+		case 'g':
+		    got++; format = tolower(*cp);
+		    nodep->v3error("Unsupported $value$plusargs format qualifier: '"<<*cp<<"'"<<endl);
+		    break;
+		default:
+		    got++;
+		    nodep->v3error("Illegal $value$plusargs format qualifier: '"<<*cp<<"'"<<endl);
+		    break;
+		}
+	    }
+	    else if (*cp == '%') pct = true;
+	    else prefix += *cp;
+	}
+	if (got!=1) nodep->v3error("Missing or extra $value$plusargs format qualifier: '"<<nodep->text()<<"'"<<endl);
+	puts("VL_VALUEPLUSARGS_I");
+	emitIQW(nodep->exprsp());
+	puts("(");
+	puts(cvtToStr(nodep->exprsp()->widthMin()));  // Note argument width, not node width (which is always 32)
+	putbs(",");
+	putsQuoted(prefix);
+	putbs(",'");
+	puts(cvtToStr(format));
+	putbs("',");
+	nodep->exprsp()->iterateAndNext(*this);
+	puts(")");
+    }
+    virtual void visit(AstTestPlusArgs* nodep, AstNUser*) {
+	puts("VL_TESTPLUSARGS_I(");
+	putsQuoted(nodep->text());
+	puts(")");
+    }
     virtual void visit(AstFGetS* nodep, AstNUser*) {
 	checkMaxWords(nodep);
 	emitOpName(nodep, nodep->emitC(), nodep->lhsp(), nodep->rhsp(), NULL);
diff --git a/src/V3EmitV.cpp b/src/V3EmitV.cpp
index 51fad083f..29df8d5b2 100644
--- a/src/V3EmitV.cpp
+++ b/src/V3EmitV.cpp
@@ -194,6 +194,9 @@ class EmitVBaseVisitor : public EmitCBaseVisitor {
     virtual void visit(AstSScanF* nodep, AstNUser*) {
 	visitNodeDisplay(nodep, nodep->fromp(), nodep->text(), nodep->exprsp());
     }
+    virtual void visit(AstValuePlusArgs* nodep, AstNUser*) {
+	visitNodeDisplay(nodep, NULL, nodep->text(), nodep->exprsp());
+    }
 
     virtual void visit(AstFOpen* nodep, AstNUser*) {
 	putbs(nodep->verilogKwd());
diff --git a/src/V3LinkLValue.cpp b/src/V3LinkLValue.cpp
index 51f0f29bd..1a625d132 100644
--- a/src/V3LinkLValue.cpp
+++ b/src/V3LinkLValue.cpp
@@ -166,6 +166,14 @@ private:
 	}
 	m_setRefLvalue = last_setRefLvalue;
     }
+    virtual void visit(AstValuePlusArgs* nodep, AstNUser*) {
+	bool last_setRefLvalue = m_setRefLvalue;
+	{
+	    m_setRefLvalue = true;
+	    nodep->exprsp()->iterateAndNext(*this);
+	}
+	m_setRefLvalue = last_setRefLvalue;
+    }
 
     // Nodes that change LValue state
     virtual void visit(AstSel* nodep, AstNUser*) {
diff --git a/src/V3Signed.cpp b/src/V3Signed.cpp
index ddccae0e6..b2949599a 100644
--- a/src/V3Signed.cpp
+++ b/src/V3Signed.cpp
@@ -86,6 +86,8 @@ private:
     virtual void visit(AstFGetS* nodep, AstNUser*) {		signed_Ou_Ix(nodep); }
     virtual void visit(AstFScanF* nodep, AstNUser*) {		signed_Ou_Ix(nodep); }
     virtual void visit(AstSScanF* nodep, AstNUser*) {		signed_Ou_Ix(nodep); }
+    virtual void visit(AstTestPlusArgs* nodep, AstNUser*) {	signed_Ou_Ix(nodep); }
+    virtual void visit(AstValuePlusArgs* nodep, AstNUser*) {	signed_Ou_Ix(nodep); }
     //
     virtual void visit(AstConcat* nodep, AstNUser*) {		signed_Ou_Ix(nodep); }
     virtual void visit(AstReplicate* nodep, AstNUser*) {	signed_Ou_Ix(nodep); }
diff --git a/src/V3Width.cpp b/src/V3Width.cpp
index 0edb3183c..88417c45b 100644
--- a/src/V3Width.cpp
+++ b/src/V3Width.cpp
@@ -753,6 +753,13 @@ private:
 	nodep->lsbp()->iterateAndNext(*this,WidthVP(ANYSIZE,0,BOTH).p());
 	nodep->msbp()->iterateAndNext(*this,WidthVP(ANYSIZE,0,BOTH).p());
     }
+    virtual void visit(AstTestPlusArgs* nodep, AstNUser* vup) {
+	nodep->width(32,32);
+    }
+    virtual void visit(AstValuePlusArgs* nodep, AstNUser* vup) {
+	nodep->exprsp()->iterateAndNext(*this,WidthVP(ANYSIZE,0,BOTH).p());
+	nodep->width(32,32);
+    }
     virtual void visit(AstUCStmt* nodep, AstNUser*) {
 	// TOP LEVEL NODE
 	// Just let all arguments seek their natural sizes
diff --git a/src/verilog.l b/src/verilog.l
index 318526504..779335011 100644
--- a/src/verilog.l
+++ b/src/verilog.l
@@ -184,8 +184,10 @@ escid	\\[^ \t\f\r\n]+
   "$sscanf"		{ FL; return yD_SSCANF; }
   "$stime"		{ FL; return yD_STIME; }
   "$stop"		{ FL; return yD_STOP; }
+  "$test$plusargs"	{ FL; return yD_TESTPLUSARGS; }
   "$time"		{ FL; return yD_TIME; }
   "$timeskew"		{ FL; return yaTIMINGSPEC; }
+  "$value$plusargs"	{ FL; return yD_VALUEPLUSARGS; }
   "$width"		{ FL; return yaTIMINGSPEC; }
   "$write"		{ FL; return yD_WRITE; }
   /*     Keywords */
diff --git a/src/verilog.y b/src/verilog.y
index 2b71097f2..633d83893 100644
--- a/src/verilog.y
+++ b/src/verilog.y
@@ -353,9 +353,11 @@ class AstSenTree;
 %token<fl>		yD_SSCANF	"$sscanf"
 %token<fl>		yD_STIME	"$stime"
 %token<fl>		yD_STOP		"$stop"
+%token<fl>		yD_TESTPLUSARGS	"$test$plusargs"
 %token<fl>		yD_TIME		"$time"
 %token<fl>		yD_UNIT		"$unit"
 %token<fl>		yD_UNSIGNED	"$unsigned"
+%token<fl>		yD_VALUEPLUSARGS "$value$plusargs"
 %token<fl>		yD_WARNING	"$warning"
 %token<fl>		yD_WRITE	"$write"
 %token<fl>		yD_aIGNORE	"${ignored-bbox-sys}"
@@ -1947,7 +1949,9 @@ system_f_call<nodep>:		// IEEE: system_tf_call (as func)
 	|	yD_SIGNED '(' expr ')'			{ $$ = new AstSigned($1,$3); }
 	|	yD_STIME				{ $$ = new AstSel($1,new AstTime($1),0,32); }
 	|	yD_TIME					{ $$ = new AstTime($1); }
+	|	yD_TESTPLUSARGS '(' str ')'		{ $$ = new AstTestPlusArgs($1,*$3); }
 	|	yD_UNSIGNED '(' expr ')'		{ $$ = new AstUnsigned($1,$3); }
+	|	yD_VALUEPLUSARGS '(' str ',' expr ')'	{ $$ = new AstValuePlusArgs($1,*$3,$5); }
 	;
 
 list_of_argumentsE<nodep>:	// IEEE: [list_of_arguments]
diff --git a/test_c/sim_main.cpp b/test_c/sim_main.cpp
index 79fa06db1..329fd322f 100644
--- a/test_c/sim_main.cpp
+++ b/test_c/sim_main.cpp
@@ -23,6 +23,7 @@ int main(int argc, char **argv, char **env) {
     if (0 && argc && argv && env) {}	// Prevent unused variable warnings
     top = new Vtop;		// Create instance of module
 
+    Verilated::commandArgs(argc, argv);
     Verilated::debug(0);
 
 #if VM_TRACE			// If verilator was invoked with --trace
diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index 1a027b6ca..72ae8ab3f 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -248,6 +248,7 @@ sub new {
 				 ))],
 	v_flags2 => [],  # Overridden in some sim files
 	v_other_filenames => [],	# After the filename so we can spec multiple files
+	all_run_flags => [],
         # IV
 	iv => 0,
 	iv_flags => [split(/\s+/,"+define+iverilog -o $self->{obj_dir}/simiv")],
@@ -495,6 +496,7 @@ sub execute {
 		    fails=>$param{fails},
 		    cmd=>["$self->{obj_dir}/simiv",
 			  @{$param{ivrun_flags}},
+			  @{$param{all_run_flags}},
 			  ]);
     }
     if ($param{nc}) {
@@ -502,13 +504,16 @@ sub execute {
 		    fails=>$param{fails},
 		    cmd=>[($ENV{VERILATOR_NCVERILOG}||"ncverilog"),
 			  @{$param{ncrun_flags}},
+			  @{$param{all_run_flags}},
 			  ]);
     }
     if ($param{vcs}) {
 	#my $fh = IO::File->new(">simv.key") or die "%Error: $! simv.key,";
 	#$fh->print("quit\n"); $fh->close;
 	$self->_run(logfile=>"$self->{obj_dir}/vcs_sim.log",
-		    cmd=>["./simv",],
+		    cmd=>["./simv",
+			  @{$param{all_run_flags}},
+		          ],
 		    %param,
 		    expect=>undef,	# vcs expect isn't the same
 		    );
@@ -518,6 +523,7 @@ sub execute {
 	) {
 	$self->_run(logfile=>"$self->{obj_dir}/vl_sim.log",
 		    cmd=>["$self->{obj_dir}/$param{VM_PREFIX}",
+			  @{$param{all_run_flags}},
 			  ],
 		    %param,
 		    );
@@ -731,6 +737,7 @@ sub _make_main {
 	print $fh "int main(int argc, char **argv, char **env) {\n";
 	print $fh "    double sim_time = $self->{sim_time};\n";
     }
+    print $fh "    Verilated::commandArgs(argc, argv);\n";
     print $fh "    Verilated::debug(".($self->{verilated_debug}?1:0).");\n";
     print $fh "    Verilated::randReset(".$self->{verilated_randReset}.");\n" if defined $self->{verilated_randReset};
     print $fh "    topp = new $VM_PREFIX (\"TOP\");\n";
diff --git a/test_regress/t/t_sys_plusargs.pl b/test_regress/t/t_sys_plusargs.pl
new file mode 100755
index 000000000..a58e3c1f8
--- /dev/null
+++ b/test_regress/t/t_sys_plusargs.pl
@@ -0,0 +1,14 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+
+compile (
+	 v_flags2 => ['-v', 't/t_flag_libinc.v'],
+	 );
+
+execute (
+	 check_finished=>1,
+	 all_run_flags => ['+PLUS +INT=1234 +STRSTR'],
+     );
+
+ok(1);
+1;
diff --git a/test_regress/t/t_sys_plusargs.v b/test_regress/t/t_sys_plusargs.v
new file mode 100644
index 000000000..c8908ed0d
--- /dev/null
+++ b/test_regress/t/t_sys_plusargs.v
@@ -0,0 +1,38 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2009 by Wilson Snyder.
+
+module t;
+
+   integer p_i;
+   reg [7*8:1] p_str;
+
+   initial begin
+      if ($test$plusargs("PLUS")!==1) $stop;
+      if ($test$plusargs("PLUSNOT")!==0) $stop;
+      if ($test$plusargs("PL")!==1) $stop;
+      //if ($test$plusargs("")!==1) $stop;  // Simulators differ in this answer
+      if ($test$plusargs("NOTTHERE")!==0) $stop;
+
+      p_i = 10;
+      if ($value$plusargs("NOTTHERE%d", p_i)!==0) $stop;
+      if (p_i !== 10) $stop;
+
+      if ($value$plusargs("INT=%d", p_i)!==1) $stop;
+      if (p_i !== 32'd1234) $stop;
+
+      if ($value$plusargs("INT=%H", p_i)!==1) $stop;  // tests uppercase % also
+      if (p_i !== 32'h1234) $stop;
+
+      if ($value$plusargs("INT=%o", p_i)!==1) $stop;
+      if (p_i !== 32'o1234) $stop;
+
+      if ($value$plusargs("IN%s", p_str)!==1) $stop;
+      $display("str='%s'",p_str);
+      if (p_str !== "T=1234") $stop;
+
+      $write("*-* All Finished *-*\n");
+      $finish;
+   end
+endmodule
diff --git a/test_regress/t/t_sys_plusargs_bad.pl b/test_regress/t/t_sys_plusargs_bad.pl
new file mode 100755
index 000000000..2495a77b9
--- /dev/null
+++ b/test_regress/t/t_sys_plusargs_bad.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); die; }
+# DESCRIPTION: Verilator: Verilog Test driver/expect definition
+#
+# Copyright 2003 by Wilson Snyder. This program is free software; you can
+# redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+
+compile (
+	 fails=>$Self->{v3},
+	 expect=>
+q{%Error: t/t_sys_plusargs_bad.v:\d+: Missing or extra \$value\$plusargs format qualifier: 'NOTTHERE'
+%Error: t/t_sys_plusargs_bad.v:\d+: Illegal \$value\$plusargs format qualifier: 'z'
+%Error: t/t_sys_plusargs_bad.v:\d+: Missing or extra \$value\$plusargs format qualifier: 'INT=%x%x'
+%Error: Exiting due to.*},
+	 );
+
+ok(1);
+1;
+
diff --git a/test_regress/t/t_sys_plusargs_bad.v b/test_regress/t/t_sys_plusargs_bad.v
new file mode 100644
index 000000000..672873cf9
--- /dev/null
+++ b/test_regress/t/t_sys_plusargs_bad.v
@@ -0,0 +1,22 @@
+// DESCRIPTION: Verilator: Verilog Test module
+//
+// This file ONLY is placed into the Public Domain, for any use,
+// without warranty, 2009 by Wilson Snyder.
+
+module t;
+
+   integer p_i;
+
+   initial begin
+      // BAD: Missing argument
+      if ($value$plusargs("NOTTHERE", p_i)!==0) $stop;
+
+      // BAD: Bad letter
+      if ($value$plusargs("INT=%z", p_i)!==0) $stop;
+
+      // BAD: Multi letter
+      if ($value$plusargs("INT=%x%x", p_i)!==0) $stop;
+
+      $stop;
+   end
+endmodule
diff --git a/test_sp/sc_main.cpp b/test_sp/sc_main.cpp
index 11bbcb90e..87114f9ce 100644
--- a/test_sp/sc_main.cpp
+++ b/test_sp/sc_main.cpp
@@ -26,6 +26,7 @@
 Vtop *top;
 
 int sc_main(int argc, char* argv[]) {
+    Verilated::commandArgs(argc, argv);
     Verilated::randReset(2);
     Verilated::debug(0);	// We compiled with it on for testing, turn it back off
 
diff --git a/test_verilated/sim_main.cpp b/test_verilated/sim_main.cpp
index 9e4d352c7..9bbdbdc90 100644
--- a/test_verilated/sim_main.cpp
+++ b/test_verilated/sim_main.cpp
@@ -19,6 +19,7 @@ double sc_time_stamp () {
 }
 
 int main(int argc, char **argv, char **env) {
+    Verilated::commandArgs(argc, argv);
     Verilated::debug(0);	// We compiled with it on for testing, turn it back off
 
     top = new Vvgen;